Welding machine



FIG. 1 is a top view of the design;

FIG. 2 is a right side view of the design;

FIG. 3 is a left side view of the design;

FIG. 4 is a front perspective view of the design;

FIG. 5 is another front perspective view of the design;

FIG. 6 is a front side view thereof;

FIG. 7 is a bottom view of the design; and,

FIG. 8 is a back view of the design.

The broken lines show portions of a welding machine that form no part of the claimed design. 

CLAIM The ornamental design for a welding machine, as shown and described. 